Improvement in casting centers on cast-iron screws



T. M. TUCKER.

Casting Centers on Cast-Iron Screws.

No 135,388. Patentedlan.28,1873.

V "RV PATENT OFFICE.

THEODORE M. TUCKER, OF NEWARK, NEW JERSEY.

IMPROVEMENT IN CASTING CENTERS ON CAST-IRON SCREWS.

Specification forming part of Letters Patent No. 135,388, dated January28, 1873.

To all whom it may concern Be it known that I, THEODORE M. TUCKER, ofNewark, in the county of Essex and State of New Jersey, have invented anImprovement in Screws and other articles of cast metal requiringturning; and I do hereby declare that the following is a .full, clear,and exact description thereof, reference being had to the accompanyingdrawing forming part of this specification.

This invention is designed mainly for use in the manufacture ofcast-iron screws used in piano-stools, revolving-chair stools, and otherarticles of furniture; but it is applicable to many other cast articleswhich require to be turned in a lathe between centers. Its object is tosave the time usually occupied in centeringH'or the lathe. To this endit consists in providing on the ends of the screws or other articles inthe casting male centers of conical form, by which they may, without anycentering process, be placed directly between the centers of the lathe,such centers, of course, being female.

The accompanying drawing is a partly sectional side View of achair-screw made according to my invention.

On one end this screwA is provided with a flange, a, by which it issecured to the seat of a chair or other article of furniture, and oneach end there is formed a male center, B, of conical form, asrepresented. These two centers B B enable the screw, as soon as cleaned,to be directly placed in a lathe for turning, without wasting any time.in forming centers. 0 represents the nut within which the screw works.It is screwed in the pedestal of the chair in the usual way.

Much time is saved'in the manufacture of these screws by obviating thenecessity for forming centers, and the cost of such articles isconsequently reduced. The invention is equally applicable andadvantageous to various other cast articles requiring to be turned.

Claim,

The male centers B B cast on a chair-screw or other cast articlerequiring to be turned between lathe-centers, substantially as and forthe purpose herein set forth.

THEODORE M. TUCKER.

\Vi tnesses:

J. WHITEHEAD, LANGDON H, GILMORE.

